2: Points, Lines, and Planes (1.3) | A point has no dimension. A line has one dimension and goes on forever in two directions. A plane has two dimensions. | Line | Plane

3: Real World Examples | A Pattern is a repeated sequence or design Example: Describe a pattern in the numbers. 5, 7, 10, 14, 19 Each number after the first is two more than the previous one. | Patterns | Real World Examples: | Example of Lines: The white lines on roads.

4: Angles and Their Measures | Right angles equal 90 degrees. | Acute angles measure between 0 and 90 degrees. | Obtuse angles measure between 90 and 180 degrees. | Straight angles measure 180. | Angles are made by two rays that have the same endpoint. Congruent Anlgles are angles that have the same measure. Angles are classified according to their measures, as shown in the picture on the left.

5: Real World Example: Architects frequently use right angles when building. The corner of a ceiling or window is a common example of a right angle. The edge of a window is a straight angle.

6: Segment and Angle Bisectors | To bisect is to divide into two equal parts. A Segment Bisector is a segment, ray, plane, or line that intersects a segment at its midpoint. An Angle Bisector is a ray that divides an angle into two congruent angles. | Angle Bisector | Segment Bisector

7: Example: | Find the length of -------- AB. Since segment AE= segment EB, the equation is: 6y=72 72 divided by 6=12 y=12 | Real World Example: | An example of a segment bisector are the bars of a fence. The bisect each other, as shown in the picture to the right.

8: Vertical | Supplementary | Complementary | Complementary, Supplementary, and Vertical Angles | Complementary Angles add up to equal 90 degrees. Supplementary Angles add up to equal 180 degrees. Vertical Angles are angles that are NOT adjacent, and their sides are formed by two intersecting lines (Vertical angles are Congruent).

9: Real World Example: | Example: Find the supplement of the angle. | Since supplementary angles add up to equal 180 degrees, and this angle is 45 degrees, its supplement would be 135 degrees. | This picture shows vertical angles in these tiles.

10: Parallel lines are lines that lie in the same plane and do not intersect. Transversals are lines that intersect two or more coplanar lines at different points. | Real World Example: The yellow lines on roads are parallel. | Corresponding Angles | Parallel Lines and Angles Formed by Transversals

11: Angles Formed by Transversals: Corresponding Angles are angles that occupy corresponding positions. Alternate Interior Angles are angles that lie between two lines on the opposite side of the transversal. Alternate Exterior Angles are angles that lie between two lines on the opposite side of the transversal. Same-Side Interior Angles are angles that lie in between the two lines on the same side of the transversal.

12: Lines are perpendicular if they intersect to form a right angle. A line perpendicular to a plane intersects a plane in a point and is perpendicular to every line in the plane that intersects it. | Perpendicular

13: Real World Example: When streets intersect they form right angles. | Lines

14: Triangles and Angle Measures | A triangle is a figure made by three segments joining three noncollinear points. | Classification of Triangles: By Sides: An Equilateral has 3 equal sides. An Isosceles has 2 equal sides. A Scalene has NO equal sides. By Angles: An Equiangular has 3 equal angles. | An Acute has 3 acute angles. A Right has 1 right angle. An Obtuse has 1 obtuse angle. | Isosceles Triangle | Right Triangle

15: Interior Angles are the angles between the adjacent sides of a triangle: Exterior Angles are angles that are adjacent to the interior angles: Theorem: m<1=m